Lorraine Hansberry's 1959 play "A Raisin in the Sun" is a classic of the American canon, a groundbreaking production that was the first Broadway show to make a serious exploration of African-American life. Yet, as well-known as it is, its author's tumultuous life - which ended too soon at the age of 34 - has sunk into the haze of history. Tracy Heather Strain's beautifully melancholic two-hour documentary, "Sighted Eyes/Feeling Heart," the kick-off for the 32nd season of "American Masters" on PBS at 8 p.m.